Vacuum control assembly for distributors



Jar 8, 1963 3,072,758

B. D. GRIBBEN ETAL VACUUM CONTROL ASSEMBLY FOR DISTRIBUTORS I soVII/fj'lfI/la 74 74 se T y- Filed Oct. 24, 1960 Fig.5

INVENTORS. Bruce 0. Gribben bl/ace 6. 8mm

Their Aflorngy United. Statesv Patent Ofifice 3,072,758 Patented Jan. 8,1963 3,072,758 VACUUM CONTROL ASSEMBLY FOR DISTRIBUTORS Bruce D. Gribbenand Wallace C. Brown, Anderson, Ind., assignors to General MotorsCorporation, Detroit,

Mich., a corporation of Delaware Filed Oct. 24, 1960, Ser. No. 64,621 10Claims. (Cl. 200-19) This invention relates to distributors for internalcombustion engines, and more particularly to improved vacuum advanceapparatus for such distributors.

One of the objects of this invention is to provide a dis tribu-tor thathas a vacuum control unit that is of a simplified construction in thatit includes a diaphragm that is simply fitted onto a flanged portion ofthe ease member to thereby provide a vacuum chamber defined by thediaphragm and case. 1

Another object of this invention is to provide a distributor' that has avacuum unit that includes a case formed. as a'plastic molded part and adiaphragm that is fitted to an annular flanged portion of the case.

I A furtherobject of this invention is to provide a distributorvacuumicontrol assembly that includes a bracket member that is securedto the distributor base, a bracket member having a U-shaped section withone leg of this .U-shaped section having a recess that receives aportion of a plastic case member and another leg, of the U-shapedsection forming a stop for the diaphragm which is fitted to an annularflanged portion of the case.

Still another object of this invention is to provide a distributorvacuum advance mechanism that has an improved range block for limitingthe vacuum advance of the distributor. i .1 Further objects andadvantages of the present invention will be apparent from the followingdescription, reference being had to the accompanying drawings wherepreferred embodiments of the present invention are clearly shown.

In the drawings:

. FIGURE 1 is a top plan viewof a distributor that is fitted with avacuum control assembly made in'accordance with this invention. a I

7 FIGURE 2 is a sectional view taken along line 22 of FIGURE 1.

FIGURE 3 is a sectional view taken along line 3- 3 of FIGURE 2. I L

- FIGURE 4 is an end view of the vacuum control assembly made inaccordance with this invention.

FIGURE 5 is a perspective view of a range block made in accordance withthis invention. I

Referring now to the drawings, and more particularly .to FIGURE 1, thereference numeral generally 'designates a distributor for controllingthe ignition of an internal combustion engine. The distributor has ametal base designated by reference'numeral 12 and this metal v basesupports a rotatable breaker plate designated by reference numeral 14.The breaker plate 14, as in conventional practice, carries a contact setgenerally designated by reference numeral 16. This contact set has theusual ,pivotally. mounted breaker arm 18 carrying the contact 20. Thecontact 20 cooperates with a fixed contact 22 as is well known to thoseskilled in the art and the breaker lever 18 has arubbirig block 24 thatengages ,a cam member 26. The cam member, as is well known to thoseskilled in the art, is driven by the distributor shaft and causes thebreaker contacts 20 and 22 to open and close in synchronisrn' withoperation of the engine.

The breaker plate 14 is rotated around the longitudinal axis of the cam26 by the vacuumcontrol assembly which is to be described. I V g Thevacuum control assembly for shifting the breaker plate 14 includes abracket member generally designated by reference numer-a'l 28. Thisbracket member is formed of a suitable metal material and it is seenthat it has a straight section 30 formed with a longitudinally extendingslot 32. The straight section 30 of the bracket member is secured to thedistributor base 12 as by the fasteners 34. The bracket member 28 has aU-shaped section defined by the legs 34 and 36 which are substantiallyparallel to each other. A slot 38 is formed in one leg 34 of thisU-shaped section and this slot has generally converging side walls 140and 142.

The vacuum power unit of the vacuum control assembly includes a moldedpart generally designated by reference numeral 40 which is formed of aplastic material such as nylon.v It can be seen that this molded part 40has a tubular conduit portion 42 and an annular flange 44. The moldedpart 40 has a plurality of strengthening ribs 46 extending along part ofthe length of this part. In addition, the molded part 40 has an internalannular portion 48 which serves as a seat for the spring 50. The

'. molded part 40 has an annular shoulder 52 which is spaced from an endwall 54 of the case 40.

The molded case 40 carries a diaphragm 56 which may be formed of rubberor other similar flexible material. The diaphragm is connected with arod 58 having an upturned portion 60 which passes through the slot 32formed in the bracket member 28. The connection between the rod 58 andthe diaphragm 56 is made by the metal washers 62 and 64 which arepositioned on opposite sides of the diaphragm and which engage the rod58. The rod 58 is headed over at 66 in orderto tightly compress thediaphragm between the washers 62 and 64 and therefore provide anair-tight connection with the end of the red member 58. It is importantto note that the diaphragm 56 has an annular section 68 that is formedwith a groove that receives the annular flanged portion 44 of the moldedcase 40. In assembling the diaphragm 56 to the molded case 40, it isonly necessary to fit the diaphragm onto the case with the annularflange snapping into the groove formed in the annular portion 68 of thediaphragm. The spring 50, as is clearly apparent from FIGURE 2, isinterposed between the end wall 54 of the case and the metal washer 62.v The spring 50 biases the diaphragm in such a direction as to force thewasher 64 into engagement with the end wall 36 of the bracket. This endwall has downwardly projecting legs 36a which also engage the washer 64to limit the movement of the diaphragm 56 in one direction. It will, ofcourse, be appreciated that when the'tubular conduit portion 42 of thecase is connected with vacuum the diaphragm is shifted rightwardly tocause a rightward movement of the rod 58. The upturned portion 60 0f therod fits within an opening formed in the breaker plate 14 and ittherefore can be seen that the. shiftable movement of the rod will causea rotatable movement of the breaker plate. V The molded case member 40is held in place by slipping the annular portion 53 of the case member.into the slot 38 formed in the leg 34 of the bracket member 28. A partof the bracket member will then be positioned between .range block whichlimits the vacuum advance of the distributor. This range block isgenerally designated by reference numeral 70 and is shown in perspectivein FIGURE 5. Therange block has a pair of lugs 72 which are each formedwith an outwardly extending tooth portion 74. The range block 70 alsohas a downwardly extending section 76.

The range block 70 is assembled to the bracket member 28 of the vacuumcontrol assembly by simply pushing the lugs 72 down through the slot 32.When the lugs are moved downwardly in the slot 32 a distance suflicientto clear the bottom edge of the portion 30 of the bracket member, theteeth snap outwardly and engage the underside of the portion 30 of thebracket member to securely hold the range block in place in the bracketmember. The range block 70 is preferably formed of a suitable plasticmaterial such as nylon and it will be apparent that when it is insertedin the slot 32 it will limit movment of the rod member 58 to somepredetermined amount in a rightward direction in FIGURE 2. This will, ofcourse, limit the amount of vacuum advance that can be achieved when therange block is used.

While the embodiments of the present invention as herein disclosed,constitute preferred forms, it is to be understood that other formsmight be adopted.

What is claimed is as follows:

1. In combination, a distributor having a base, a breaker plateshiftable relative to said base, breaker contact means carried by saidbreaker plate, a vacuum control assembly including a bracket member,said bracket member having a section secured to said base and having agenerally U-shaped section, a case member formed of moldable plasticmaterial having an annular flanged portion, a diaphragm fitted to saidannular flanged portion, a spring member located between a portion ofsaid case member and said diaphragm, said case member and diaphragmbeing positioned between two of the legs of the U-shaped section withone of the legs limiting movement of the diaphragm in one direction,means securing the case member to the other of said legs, and a rodmember connecting said diaphragm and said breaker plate.

2. A vacuum control assembly for shifting the breaker plate of adistributor comprising, a bracket member having a section that isadapted to be secured to the base of the distributor and a generallyU-shaped section, a case member formed of a moldable plastic materialhaving an open end, said case member having an annular flanged portion,a diaphragm having an annular extending groove receiving the annularflanged portion of said case member and closing the open end of saidcase member, a slot in one of the legs of the U-shaped section of saidbracket member, said slot receiving a portion of said case member tosupport one end of said case member, said bracket member having anotherportion limiting movement of said diaphragm in one direction under theinfluence of spring means interposed between said case member anddiaphragm, and a rod member connected with said dia: phragm.

3. A vacuum control assembly for actuating the breaker plate of adistributor comprising, a bracket member having a section adapted to besecured to the base of the distributor, a case member formed of amoldable plastic material having an open end, said case member having anannular extending flange, a diaphragm formed with an'annular groovereceiving the annular flange of said case member and closing the openend of said case member, conduit means connecting the interior of saidcase member with the exterior thereof, a spring interposed between saiddiaphragm and one end of said case member for urging said diaphragm inone direction, a slot formed in a portion of said bracket member, saidslot receiving a section of said case member and being positionedbetween an end wall of said case member and an annular extending portionof said case member to fix said case member from movement relative tosaid bracket member, said bracket member having another section limitingmovement of said diaphragm in one direction under the influence of saidspring, and a rod member connected with said diaphragm.

4. A vacuum control assembly for actuating a breaker plate of adistributor comprising, a case member formed of a moldable plasticmaterial having an open end, said case member having an annular flange,a diaphragm closing said open end and including an annular groovereceiving said annular flange, a bracket member having a first sectionthat is adapted to be secured to the base of the distributor, saidbracket member having a second second section formed with a slot, saidcase member having a section fitting within said slot and havingsections positioned on opposite sides of the second section of saidbracket member for securing one end of said case member to said bracketmember, passage means formed in said case member passing through theslot formed in the second section of said bracket member, said bracketmember having integral means limiting movement of said diaphragm in onedirection under the influence of a spring that is interposed between onewall of said case member and said diaphragm, and a rod member connectedwith said diaphragm. V

5. In combination, a distributor having a base, a break! er plateshiftable relative tosaid base member, breaker contact means carried bysaid breaker plate, a bracket member secured to said base having a slot,a rod member shiftable in said slot and connected with said breakerplate for shifting the same, vacuum power means for shifting said rodmember, and a range block positioned within said slot for limitingmovement of said rod memher in one direction, said range block having apair of lugs passing through said slot and having teeth engaging aportion of said bracket member.

6. In combination, a distributor having a base, a break er plateshiftable relative to said base, breaker contact means carried by saidbreaker plate, a bracket member secured to said base having a slot, arod member shiftable in said slot and connected with said breaker platefor shifting the same, vacuum power means for shifting said rod, and arange block fitted within said slot for limiting movement of said rod inone direction, said range block being formed of a plastic material andhaving means that snap under one wall of the bracket member when theblock is fitted within said slot.

'7. In combination, a distributor having a base, a break-- er plateshiftable relative to said base, breaker contact means carried by saidbreaker plate, a bracket member secured to said base, said bracketmember having a slot formed with side walls and end walls, a rod membershiftable in said slot and connected with said breaker plate forshifting the same, vacuum power means for shifting said rod member, anda range block fitted within said slot engaging one of said end walls forlimiting movement of said rod member in one direction. 7

8. In combination, a distributor having a base, a breaker plateshiftable relative to said base, breaker contact means carried by saidbreaker plate, a bracket member secured to said base, said bracketmember having a slot, 9. rod member shiftable in said slot and connectedwith said breaker plate for shifting the same, vacuum power means forshifting said rod'member, and a range block having lugs passing throughsaid slot and having portions engaging one side of said bracket memberforpreventing removal of said range block from said bracket member, saidrange block limiting movement of said rod member in one direction andhaving a portion in sliding engagement with said rod member.

9. In combination, a distributor having a base, a break er plateshiftable relative to said base, breaker contact means carried by saidbreaker plate, a vacuum control assembly, said vacuum. control assemblyincluding a generally cup-shaped housing having an open end, said cupshaped housing having an annular flanged portion, a diaphragm having anannular groove receiving the annular flanged portion of said cup-shapedhousing enclosing the open end of said cup-shaped housing, said flangedportion and groove forming the sole means for securing said diaphragm tosaid cup-shaped housing, a unitary bracket member having a portionsecured to said base member, 1

said bracket member having a first integral portion supporting one endof said cup-shaped housing and having a second integral portion servingas a stopmeans for said diaphragm, said second integral portionperforming no clamping function on said diaphragm, and a rod memberconnecting said diaphragm and said breaker plate.

10. The combination according to claim 9 wherein the cup-shaped housingis formed of a moldable plastic material.

References Cited in the file of this patent UNITED STATES PATENTSHardrnan Dec. 23, 1930 White Aug. 4, 1936 Arthur et a1 Sept. 27, 1938Ostling June 14, 1949 Hartzell et a1 Oct. 30, 1956 Clason June 4-, 1957

1. IN COMBINATION, A DISTRIBUTOR HAVING A BASE A BREAKER PLATE SHIFTABLERELATIVE TO SAID BASE, BREAKER CONTACT MEANS CARRIED BY SAID BREAKERPLATE, A VACUUM CONTROL ASSEMBLY INCLUDING A BRACKET MEMBER, SAIDBRACKET MEMBER HAVING A SECTION SECURED TO SAID BASE AND HAVING AGENERALLY U-SHAPED SECTION, A CASE MEMBER FORMED OF MOLDABLE PLASTICMATERIAL HAVING AN ANNULAR FLANGED PORTION, A DIAPHRAGM FITTED TO SAIDANNULAR FLANGED PORTION, A SPRING MEMBER LOCATED BETWEEN A PORTION OFSAID CASE MEMBER AND SAID DIAPHRAGM, SAID CASE MEMBER AND DIAPHRAGMBEING POSITIONED BETWEEN TWO OF THE LEGS OF THE U-SHAPED SECTION WITHONE OF THE LEGS LIMITING MOVEMENT OF THE DIAPHRAGM IN ONE DIRECTION,MEANS SECURING THE CASE MEMBER TO THE OTHER OF SAID LEGS, AND A RODMEMBER CONNECTING SAID DIAPHRAGM AND SAID BREAKER PLATE.